July 10, 2024

Physics-informed tracking of qubit fluctuations 

In this latest research from Prof. Ferdinand Kuemmeth's lab at NBI, a physics-informed and real-time Hamiltonian estimation protocol is applied to a qubit. This protocol estimates the fluctuating environment of a spin qubit (a nuclear spin bath) on-the-fly on the OPX quantum controller, by updating its probability distribution according to the model describing the nuclear spins (Fokker-Planck equation). It is further improved by adaptively choosing the probing time of the qubit based on the previous measurement outcomes, to maximize the information gathered per measurement (arXiv:2404.09212).

The agenda included two parts: 

1. Part I (Fabrizio Berritta, NBI): Overview of the latest research from Ferdinand's lab at NBI.
2. Part II (Fabio Ansaloni, QM): Quantum dots research with OPX and QDAC use case.
   
   

• Fabio Ansaloni,
  PhD, Research scientist, Quantum Machines
  Fabio, currently a Research Scientist at Quantum Machines, previously conducted pioneering research as a Postdoctoral Researcher at Princeton University. With a PhD from Niels Bohr Institute, University of Copenhagen, his expertise spans spin qubit technology and low-temperature operation of quantum devices.

   

  
  Fabrizio Berritta,
  PhD student, Center for Quantum Devices, Copenhagen University
  Fabrizio joined the Center for Quantum Devices in October 2020 as a PhD student supervised by Prof. Ferdinand Kuemmeth. Research deals with the experimental implementation of spin qubit processors using high-frequency and field-programmable gate-array-based techniques.

For any follow-up questions: fabio@quantum-machines.co.